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Biomedical subjects

D Campbell

Publications and source records attributed to D Campbell.

At least 253 records · Page 14Linked to original sources
PubMed1988

Growth potential of human colorectal carcinomas in nude mice: association with the preoperative serum concentration of carcinoembryonic antigen in patients.

A preoperative serum carcinoembryonic antigen (CEA) concentration greater than 5 ng/ml portends a poor prognosis for patients with colorectal carcinoma. The purpose of this study was to determine if the tumorigenicity of colorectal carcinomas in nude mice was associated with the preoperative serum CEA concentration. Neoplasms from 53 patients were either implanted as fragments or dissociated with collagenase and DNase, and 3 x 10(6) viable cells were injected into the flanks of BALB/c nude mice. The growth potential of tumors resected from patients with CEA levels exceeding 5 ng/ml was greater than that of tumors from patients with normal serum CEA: 26 of 33 carcinomas from patients with CEA greater than or equal to 5 ng/ml were tumorigenic in nude mice, whereas only 8 of 22 neoplasms from patients with normal serum CEA were tumorigenic in nude mice (P less than 0.001). Primary colorectal cancers, not metastases, were the basis for the association between tumorigenicity and preoperative CEA. Tumorigenicity was also associated with stage of disease, since Dukes' D primary tumors and metastases were more tumorigenic than Dukes' A to C primary tumors. Growth in nude mice was not associated with other prognostic factors such as tumor site, mucin production, local invasion, or stage of histological differentiation. The tumorigenic capability of human colorectal carcinomas may be associated with the preoperative serum CEA concentration and may reflect an increased potential to develop clinical metastases.

Adult↗
PubMed1988

High-resolution 13C NMR study of pressure effects on the main phase transition in L-alpha-dipalmitoyl phosphatidylcholine vesicles.

The effects of pressure on the liquid-crystalline to gel transition in vesicles of L-alpha-dipalmitoyl phosphatidylcholine were investigated by high-resolution proton-decoupled natural-abundance 13C NMR spectroscopy. The linewidths of several 13C resonances, including the choline methyl groups, carbonyl carbons, and choline methylene groups and the palmitoyl methyl groups are reported as a function of pressure at 52.7 degrees C. These preliminary NMR experiments clearly demonstrate that high-pressure, high-resolution proton-decoupled natural-abundance 13C NMR spectra are a promising tool to study the phase-transition behavior and the dynamics of model membrane systems.

1,2-Dipalmitoylphosphatidylcholine↗
PubMed1988

Developmental Regulation of Enzymes of Indole Alkaloid Biosynthesis in Catharanthus roseus.

Developing seedlings of Catharanthus roseus were analyzed for appearance of tryptophan decarboxylase (TDC), strictosidine synthase (SS), N-methyltransferase (NMT) and O-acetyltransferase (DAT) enzyme activities. SS enzyme activity appeared early after germination and was present throughout most of the developmental study. TDC activity was highly regulated and peaked over a 48 hour period achieving a maximum by day of 5 of seedling development. Both TDC and SS were present in all tissues of the seedling. NMT and DAT enzyme activities were induced after TDC and SS had peaked and these activities could only be found in hypocotyls and cotyledons. TDC, SS, and NMT did not require light for induction whereas DAT enzyme activity was increased approximately 10-fold after light treatment of dark grown seedlings.

Journal Article↗
PubMed1988

Effects of ketamine on liver blood flow and hepatic oxygen consumption. Studies in the anaesthetised greyhound.

The effects of three increasing doses of ketamine on the blood flow to, and oxygen consumption of, the liver, were studied in seven anaesthetised greyhounds. Hepatic arterial and portal venous blood flows were measured continuously using electromagnetic flow probes, and mean arterial pressure and cardiac output monitored as appropriate. Ketamine, even at the highest dose, had little effect on the blood flow to the liver: hepatic arterial blood flow and portal venous blood flow did not differ significantly from their baseline values. However, the oxygen delivery to the liver decreased due, probably, to an increase in oxygen consumption by the pre-portal organs.

Anesthesia, Intravenous↗
PubMed1987

Necrotizing sarcoid granulomatosis.

We report a patient with necrotizing sarcoid granulomatosis (NSG) and point out that while the latter may have certain histological and radiological features distinct from sarcoidosis, sophisticated immunological tests show that the two disorders have essentially similar underlying immune mechanisms. We also stress that although the clinical course of NSG has been repeatedly described as benign and responsive to steroid therapy, the young patient may initially be critically ill with symptoms suggestive of an infective process rather than a granulomatous cause.

Adult↗
PubMed1987

Bovine achondrogenesis: evidence for defective chondrocyte differentiation.

A survey study of growth cartilage abnormalities in bovine bone dysplasias revealed that a disorder in Holstein cattle called bulldog calf closely resembles human achondrogenesis Type II. Substantial amounts of Type I collagen and other non Type II collagens were detected in the bulldog cartilage which was comprised primarily of extensive vascular canals and cells having the characteristics of hypertrophic and degenerative chondrocytes normally found in the growth plate. It is proposed that chondrocytes throughout the bulldog growth cartilage prematurely differentiate into hypertrophic cells that degenerate and predispose the cartilage to vascular invasion and the formation of cartilage canals. The presence of these canals probably accounts for most of the observed collagen abnormalities.

Animals↗
PubMed1987

The diagnosis and treatment of brown recluse spider bites.

We reviewed our experience with 95 patients who carried the diagnosis of brown recluse spider bite between 1983 and 1986 and identified a reference group of 17 with confirmed bites. Eight men and seven women, average age 32 years, presented within 33 hours following the bites. The most common symptoms were pain, pruritus, malaise, chills, sweats, and rash. Patients were randomized into three treatment groups: dapsone, brown recluse spider antivenom, or combination therapy. All patients were treated with erythromycin. If two patients with very severe lesions were excluded, patients in all groups healed their wounds in an average of 20 days. A comparison of our treatment was attempted with all other bites previously confirmed in the literature, but historical data were incomplete and no conclusions could be drawn.

Adult↗
PubMed1987

Does the use of oral contraception depress DZ twinning rates?

Data based on total births from a geographically defined population with zygosity determined from blood samples and placentation and with data on the use of oral contraceptives routinely collected in early pregnancy showed no association between oral contraceptive use prior to pregnancy in either MZ or DZ twinning. Three mutually exclusive control groups of singletons were used to take account of age, parity and secular trends.

Birth Rate↗
PubMed1987

Paramedic perception of elapsed field time.

An independent observer was placed with city paramedic teams to: a) record exactly how long emergency field procedures take; and b) determine the paramedic's perception of elapsed field time. One hundred eighteen runs were monitored; 33% required advanced life support skills, and 36% were for trauma. The response time (mean +/- S.E.M.) averaged 5.4 +/- 0.26 min, scene time 11.2 +/- 0.54 min, and transport time 9.5 +/- 0.86 min. The average time required to perform scene procedures ranged from 1.5 +/- 0.5 min for defibrillation to 5.0 +/- 0.47 min to start an IV. Paramedic perception of elapsed time for the entire run varied from the actual time by an average absolute value of 20%, with the greatest errors occurring in scene time estimates. Paramedics tended to overestimate elapsed time during short runs, and underestimate time on long runs. This report provides realistic field procedure times for urban paramedics. Distortion of time perception in the field environment emphasizes the need for strict medical control.

Allied Health Personnel↗